Get binstubs working on Windows.

sdk/lib/_internal/pub_generated/test/global/binstubs/removes_when_deactivated_test.dart

 import 'package:scheduled_test/scheduled_test.dart';
 import '../../descriptor.dart' as d;
 import '../../test_pub.dart';
+import 'utils.dart';
 main() {
   initConfig();
   integration("removes binstubs when the package is deactivated", () {
     servePackages((builder) {
       builder.serve("foo", "1.0.0", pubspec: {
         "executables": {
           "one": null,
           "two": null
         }
       },
           contents: [
               d.dir(
                   "bin",
                   [
                       d.file("one.dart", "main(args) => print('one');"),
                       d.file("two.dart", "main(args) => print('two');")])]);
     });
     schedulePub(args: ["global", "activate", "foo"]);
     schedulePub(args: ["global", "deactivate", "foo"]);
     d.dir(
         cachePath,
-        [d.dir("bin", [d.nothing("one"), d.nothing("two")])]).validate();
+        [
+            d.dir(
+                "bin",
+                [d.nothing(binStubName("one")), d.nothing(binStubName("two"))])]).validate();
   });
 }